Where does energy come from to run the economy? See trend chart for 150 years.

Courtesy of Zerohedge, with total energy in any year normalized to 100%.
It's interest how stable the coal percent is for the last seventy years.  The oil dominance is relatively recent, since WW2.  We sometimes forget how important muscle has been (and the former importance of slavery).  Despite the hype about solar and wind power which is tossed in with nuclear power, its share in the economy is minor and stable.  Gas is trending to number one.

A note about muscle power:
A few years ago I saw it used to unload motor canoes in the upper Amazon with goods being tossed uphill up a human chain.. Now think about the House of Windsor with its kings and queens.  What does "windsor" mean?  It refers to a similar dock hundreds of years ago in Britain with an astonishing innovation: A winding tool with a rope that could raise loads from the boats.  Replacing muscle is the big revolution and it is only in modern times that this was baked into the pie.  And in England the rulers are named after the only place that had a windlass a thousand years ago.